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We conceive the future as flowing every moment nearer us, and the past as retiring. An equal distance, therefore, in the past and in the future, has not the same effect on the imagination; and that because we consider the one as continually encreasing, and the other as continually diminishing. —Hume (1739/1969, p. 478) Time flies. Time marches on. Time flows like a river. Many metaphors exist to describe the passage of time. The most common, perhaps, is the “arrow of time, ” which implies both movement and direction. People move from the past toward the future; events approach from the future and recede into the past. A common theme in such metaphors is that the descrip-tions of time are grounded in the sensory experiences of spa-tial movement. In this article, we reason that the experience of movement through time is analogous to the experience of movement through space. We hypothesize that the spatial metaphor of events in time implies a fundamental asymmetry in the psychological dis-tance of past and future events: Future events are psychologi-cally closer to the present than are past events of equivalent objective distance. Because, as Hume observed, “we conceive the future as flowing every moment nearer us, and the past as retiring ” (pp. 188–189), the distance between the self and future events diminishes, whereas the distance between the self and past events increases. Just as diminishing spatial sepa-ration makes objects seem spatially closer and increasing spa-tial separation makes objects seem spatially more distant, diminishing temporal separation makes events seem tempo-rally closer and increasing temporal separation makes events seem temporally more distant. The existence of this temporal asymmetry may have important implications for theories of psychological distance that assume temporal symmetry (e.g., Trope & Liberman, 2010) and for theories of episodic memory that assume that people remember the past in largely the same way that they imagine the future (e.g., Addis, Wong, &amp